Association between Ureteral Clamping Time and Acute Kidney Injury during Robot-Assisted Radical Cystectomy.

Robot-assisted radical cystectomy (RARC) is replacing open radical cystectomy (ORC) and requires clamping of the ureters, resulting in a predisposition to postrenal acute kidney injury (AKI). We investigated the association between ureteral clamping or its duration and acute/chronic postoperative kidney function. Patients who underwent radical cystectomy (robotic or open) at two tertiary institutions during 2002-2021 were retrospectively enrolled. In those who underwent RARC, the maximum postoperative percentage serum creatinine level (%sCre) change was plotted against ureteral clamping duration. They were divided into two groups using the median clamping time (210 min), and the maximum %sCre change and percentage estimated glomerular filtration rate (%eGFR) change at 3-6 months (chronic) were compared between the ORC (no clamp), RARC < 210, and RARC ≥ 210 groups. In 44 RARC patients, a weak correlation was observed between the duration of ureteral clamping and %Cre change (R2 = 0.22, p = 0.001). Baseline serum creatinine levels were comparable between the groups. However, %sCre change was significantly larger in the RARC ≥ 210 group (N = 17, +32.1%) than those in the RARC < 210 (N = 27, +6.1%) and ORC (N = 76, +9.5%) groups (both, p < 0.001). Chronic %eGFR change was comparable between the groups. Longer clamping of the ureter during RARC may precipitate AKI; therefore, the clamping duration should be minimized.